BMW began as Rapp Motorenwerke GmbH, an engine manufacturing company founded by by Karl Friedrich Rapp in 1913. Rapp Motorenwerke GmbH built V12 airplane engines for Austro-Daimler through 1916, when Karl Friedrich Rapp (1882—1962) merged with Nikolaus August (Gustav) Otto (1883—1926) of Bayerische Flugzeugwerke AG (aka: BFW or “Bavarian Aircraft Works”). The merged company was renamed Bayerische Motoren Werke GmbH, which is commonly known as the “Bavarian Motor Works,” or “BMW.”

By 1918, Germany was loosing WWI, and an armistice was declared, leading to the Treaty of Versailles in 1919. Under the terms of the treaty, Germany was to abandon its Air Force, leaving manufacturers like BMW AG to build civilian, non-aviation products. BMW AG began by manufacturing agricultural machinery, office furniture and toolboxes.

The Chief Design Engineer at BMW during this period was Max Friz, who started out as a mechanical engineer specializing in engine design for the Kuhn Steam Engine company in Cannstatt. By 1922, Friz convinced BMW to turn its attention to motorcycle engines, built for Victoria Motorcycles in Nürnberg. The Victoria/BMW engine was a 6.5hp 494cc two-cylinder, side-valve horizontally-opposed ‘flat-twin’ engine that was to be a model for future BMW ‘boxer’ engines.

BMW’s first complete motorcycle was the 1920 ‘Flink’ which had a 148cc Kurier two-stroke engine. In 1921 BMW built the ‘Helios’ using an in-house M2B15 engine. Neither were great sellers, and the improved ‘BMW R32′ began production in 1923.

BMW R32 (1923 to 1926)

The R32 also had a flat-twin two-cylinder side-valve ‘boxer’ engine design. The 494cc R32 had an exposed ‘cardan’ driveshaft final drive, and a three-speed transmission. The chassis had a rigid tubular-frame with sprung seat, and twin-cantilever front suspension.

1923 BMW R32 494 cc Horizontally-Opposed Twin

The flat-twin engine’s longitudinal crankshaft enabled the final drive-shaft to be driven directly from the gearbox. There was no front brake on the original R32, and the rear brake was a large friction-type ring mounted to the rear wheel, that was slowed by wooden blocks.

The R32’s two-cylinder four-stroke ‘boxer’ engine produced 8.5 hp at 3,200 rpm, generating a top speed of 60 mph (96 km/h). A total of 3,090 units were produced in the R32’s 3 year production cycle.

In 1925, BMW introduced the 250cc R39, using its first proprietary single-cylinder engine. All BMW motorcycles were manufactured at the BMW Motorradwerke’s factory in München (Munich), where over 440,000 motorcycles were built between 1922 and 1969, when the motorcycle factory was moved to Berlin.

BMW R63 (1928 to 1929)

The BMW R63 series began in 1928, with a 735 cc flat twin M60 boxer engine, exposed driveshaft, and three-speed gearbox. The chassis had a rigid tubular-frame with ‘sprung-seat’ rear suspension, and six laminae plate-spring (trailing link) front suspension.

1929 BMW R63 750

The R63’s two-cylinder four-stroke ‘boxer’ engine produced 24 hp at 4,000 rpm, generating a top speed of 74 mph (120 km/h). Only 794 units were produced in the R68’s 2 year production cycle.

BMW R63 750cc Horizontal Twin Boxer Motor

1932 was the first year that BMW used dual carburetors. By 1935, all BMW motorcycles were equipped with a rear drum brake, and by 1937, BMW introduced its first foot-controlled gearbox.

In 1939, BMW acquired the BRAMO Brandenburg Motor Works factory in Berlin, and began building military aircraft engines for the Junkers JU52 at the facility.
BMW R51, R51/2, R51/3, R6 (1938 to 1954)

At the close of WWII, factories that produced German aircraft and aircraft parts were systematically dismantled, and BMW used the factory for menial civilian products or spare parts.

BMW R60/2 (1956 to 1969)

The BMW R60/2 (aka “Slash-2″) had an enclosed driveshaft, plunger rear suspension, and ‘Earles’ front fork suspension. The triangular Earles fork design is a type of leading-link suspension that was designed to work well when used in conjunction with a side-car.

1967 BMW R60/2 600 594cc OHV Horizontal Twin

The Earles fork helped to prevent front-end dive during braking, and was the precursor to BMW’s Saxon-Motodd ‘telelever’ fork assembly.

1968 BMW R60/2 with Steib Sidecar

The R60/2’s two-cylinder four-stroke boxer engine produced 30 hp at 5,800 rpm, generating a top speed of 90 mph (145 km/h). The original North American retail price for the R60/2 between $1,131 to $1,364.

BMW R69S (1960 to 1969)

The R69S began production in 1960. The R69S’s 594cc OHV boxer engine produced 42 hp at 7,000 rpm, generating a top speed of 108 mph (175 km/h). The R69S had a 4-speed transmission with an enclosed driveshaft, ‘Earles’ front fork suspension, and plunger rear suspension.

BMW R69S Restoration Photos

The 1969 model R69S was one of the last motorcycles to be produced at the Munich factory. Starting in 1966, motorcycle production was incrementally moved from Munich to the ‘Am Juliusturm’ facility in Berlin, and by 1969 all motorcycle production – with the exception of BMW’s GETRAG transmission, which is built in Ludwigsburg – was located in Berlin.